Duff CO, A General Engineering Contractor in Ione, CA
Duff CO operating as a sole owner holds an active California contractor license (CSLB #742203), valid through Nov 30, 2027. First issued in 1997, the license has been on the CSLB roster for 29 years. It carries 2 CSLB classifications: A General Engineering Contractor and C-31 Construction Zone Traffic Control Contractor. Records show an active surety bond on file with American Contractors Indemnity Company and an exempt workers' compensation status (no employees on payroll). The business is based in Ione, in Amador County, California.
- License Number
- 742203
- Issued
- Nov 4, 1997
- Status
- CLEAR
- Expires
- Nov 30, 2027
- Entity
- Sole Owner
- Surety
- American Contractors Indemnity Company
- Bond Number
- SC6029652
- Effective
- Jan 1, 2023
- Status
- Active
- Coverage
- Exempt
- Carrier
- —
- Policy Number
- —
- Effective
- Oct 9, 2025
- Expires
- —
This contractor warrants a closer look before contracting:
- Workers' comp listed as exempt
An automated summary of public CSLB data, not a credit score, rating, or endorsement. How we determine this
Is Duff CO licensed in California?
Yes. Duff CO holds California Contractors State License Board license number 742203, which is active and in good standing. The license was first issued on November 4, 1997. It is valid through November 30, 2027.
What does Duff CO specialize in?
Duff CO is licensed for 2 CSLB classifications: A General Engineering Contractor and C-31 Construction Zone Traffic Control Contractor.
Where is Duff CO headquartered?
Duff CO is headquartered at 400 Canterbury Court, Ione, CA 95640, in Amador County, California.
Does Duff CO have an active surety bond on file with CSLB?
Yes. Duff CO has an active California contractor surety bond filed with American Contractors Indemnity Company.
Does Duff CO carry workers' compensation coverage?
Duff CO reports an exempt workers' compensation status, meaning the business has no employees on payroll.
How do I verify Duff CO's contractor license?
You can verify Duff CO's license directly with the California Contractors State License Board at https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=742203.
- License issuedNov 4, 1997
- Bond activeJan 1, 2023
- WC coverage startsOct 9, 2025
- License expiresNov 30, 2027
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